• KCID journal
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• v.18 no.2
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• pp.66-75
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• 2011

Multivariate statistical analysis was applied to 110 dam heightening reservoir to classify the building conditions for waterfront centered around cultivated area using data of land cover, landscape, additional water quantity, local economic, tourism resources, and accessibility related variables. Five factors were extracted through factor analysis based on eigen value criteria of more than one. These five factors together account for 68.2% of the total variance. Characteristics of five factors for the downstream of dam heightening reservoirs are building conditions of waterfront, economic conditions, additional water quantity, eco-tours, and accessibility of tourism resources respectively. Five clusters were classified through cluster analysis based on factor score. The classified result shows that third cluster has remunerative terms for building waterfront.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.390-396
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• 2000

The basic concept of the model is minimizing the error range between forecasted flood inflow and actual flood inflow, and accurately forecasting the flood discharge some hours in advance depending on the concentration time(Tc) and soil moisture retention storage(Sa). Simplex method that is a multi-level optimization technique was used to search for the determination of the best parameters of RETFLO (REal-Time FLOod forecasting)model. The flood forecasting model developed was applied to several strom events of Yedang reservoir during past 10 years. Model perfomance was very good with relative errors of 10% for comparison of total runoff volume and with one hour delayed peak time.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.512-518
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• 1999

Recently rainfall and water evel are monitored via on -line system in real-time bases. We applied the on-line system to get the rainfall and waterlevel data for the development of the real-time flood forecasting model based on SCS method in hourly bases. Main parameters for the model calibration are concentration time of flood and soil moisture condition in the watershed. Other parameters of the model are based on SCS TR-%% and DAWAST model. Simplex method is used for promoting the accuracy of parameter estimation. The basic concept of the model is minimizing the error range between forcasted flood inflow and actual flood inflow, and accurately forecasting the flood discharge some hours in advance depending on the concentration time. The flood forecasting model developed was applied to the Yedang and Topjung reservoir.

• KCID journal
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• v.13 no.1
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• pp.72-81
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• 2006

The objictive of this study is to analyze regional drought using agricultural drought indicator. Toforecast and evaluate the drought, the drought indices for agriculture were applied. In the present drought preparedness plans of Ministry of Agriculture and Forestry (MAF), it is prescribed that the preparedness levels should be classified by considering the precipitation, reservoir storage, soil moisture in paddy and upland, and the growing status of crops. There are many drought index to analyze and evaluate the drought. However, these indices do not exactly explain all drought events. Thus, we select 4 drought indices to evaluate agricultural drought:reservoir storage index, 3-month delayed SPI, mean rainfall index, and dry day index. Using these ineices, six drought stages are classified. The results show that agricultural drought could be apprppriately analyzed and evaluated by agricultural drought stage and four drought indices.

• Journal of Korea Water Resources Association
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• v.37 no.1
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• pp.77-86
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• 2004

This paper presents a reservoir operation plan coupled with storage forecasting model to maintain a target storage and a critical storage. The observed storage data from 1990 to 2001 in the Geum-Gang agricultural reservoir in Korea have been applied to the low flow frequency analysis, which yields storage for each return period. Two year return period drought storage is then designated as the target storage and ten year return period drought storage as the critical storage. Storage in reservoir should be forecasted to perform reasonable reservoir operation. The predicted storage can be effectively utilized to establish a reservoir operation plan. In this study the autoregressive error (ARE) model and the ARIMA model are adopted to predict storage of reservoir. The ARIMA model poorly generated reservoir storage in series because only observed storage data were used, but the autoregressive error model made to enhance the reliability of the forecasted storage by applying the explanation variables to the model. Since storages of agricultural reservoir with respect to time have been affected by irrigation area, high or mean temperature, precipitation, previous storage and wind velocity, the autoregressive error model has been adopted to analyze the relationship between storage at a period and affecting factors for storage at the period. Since the equation for predicting storage at a period by the autoregressive error model is similar to the continuity equation, the predicting storage equation may be practical. The results from compared the actual storage in 2002 and the predicted storage in the Geum-Gang reservoir show that forecasted storage by the autoregressive error model is reasonable.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.2
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• pp.255-263
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• 2010

In order to prepare the interchange between and the unification of North and South Korea, it is needed to establish the development direction of irrigation reservoirs and formulate technological and political directions for preparing effectively against the demand of agricultural countermeasure information like the analysis of rural comprehensive development projects and the present state of agricultural land of North Korea. The purpose of this research is to construct the database of agricultural productive infrastructures and analyze the present state of irrigation reservoirs of the Yeseong River Basin in North Korea using SPOT-5 satellite imagery. As a result of the research, we were able to not only design classification items but establish method and precedure for producing thematic maps related agricultural productive infrastructure without on-site survey by analyzing present condition related to agricultural water of the basin. And we intend to provide basic data for analyzing suitabile locations of irrigation reservoirs in the basin by performing basin extraction, volume evaluation of the existing reservoirs, scale cultivative lands, benefit area fo the reservoirs, and the existing agricultural water system. In addition, we were able to understand the problem and limit in constructing the database related agricultural productive facilities.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.2
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• pp.11-23
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• 2014

The impact and adaption on agricultural water resources considering climate change is significant for reservoirs. The change in rainfall patterns and hydrologic factors due to climate change increases the uncertainty of agricultural water supply and demand. The quantitative evaluation method of uncertainty based on agricultural water resource management under future climate conditions is a major concern. Therefore, it is necessary to improve the vulnerability management technique for agricultural water supply based on a probabilistic and stochastic risk evaluation theory. The objective of this study was to analyse the uncertainty of water resources under future climate change using probability distribution function of water supply in agricultural reservoir and demand in irrigation district. The uncertainty of future water resources in agricultural reservoirs was estimated using the time-specific analysis of histograms and probability distributions parameter, for example the location and the scale parameter. According to the uncertainty analysis, the future agricultural water supply and demand in reservoir tends to increase the uncertainty by the low consistency of the results. Thus, it is recommended to prepare a resonable decision making on water supply strategies in terms of using climate change scenarios that reflect different future development conditions.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.13-24
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• 2013

Agriculture is affected directly by climate conditions and changes, and it is necessary to understand the impact of climate change on agricultural reservoirs which are the main water resources for paddy fields in Korea. This study aimed to evaluate the impact of climate change on the anti-drought capacity including water supply capability (WSC) and drought response ability (DRA) of agricultural reservoirs based on RCP (Representative Concentration Pathway) 4.5 and 8.5 scenarios of CanESM2 (The Second Generation Earth System Model) provided by CCCma (Canadian Center for Climate Modeling and Analysis). The WSC and DRA were estimated using frequency analysis and runs theory. The six reservoirs (Yooshin, Nogok, Kumsung, Songgok, Gapyung, Seoma) were selected considering geographical characteristics and design criteria of reservoir capacity. In case of Seoma reservoir, more than 10 year drought return period (DRP), the variation of the WSC was estimated larger than the others. In case of Yooshin reservior (2~5 DRP) DRC was decreased in 2025s under RCP8.5. These results could be utilized for agricultural reservoirs management and future design criteria considering climate change impacts on paddy irrigation.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.372-372
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• 2012

해외 사업에서 지구에 따라 기상 자료가 부족한 지역이 많다. 여기서는 에티오피아의 밭 관개 용수 공급을 위해 일 강우 자료와 월평균 기상자료를 이용하여 일 증발 자료를 생산하여 적정 저수지 위치와 규모를 정한 결과 다음과 결과를 얻었다. 첫째, 구글지도와 DEM을 이용하여 6개의 댐 후보지를 선정하였고, 표고별 저수면적, 저수량 관계식을 도출하였다. 둘째, 기상자료 수집의 어려움으로 한국 자료를 분석하여 현지의 장기간 기상 자료를 가공, 모의하여 적용하였다. 셋째, 현지 유량측정 자료와 한국 관측자료를 이용하여 현지의 합리적인 일 유입량 자료를 생산하였다. 넷째, 현지의 토양조건을 고려하고, 토양수분 물수지 모형을 개발하여 토양수분 부족량 공급 기준의 합리적 관개용수 필요수량을 산정하였다. 다섯째, 저수지 일 물수지 모형을 구축하여, 저수량 일별 모의에 의해 적정 댐 저수지 규모를 결정하였다. 여섯째, 국내 농업용 저수지의 실적 공사비 내역 자료를 참고하여 합리적 수준의 개략 공사비와 총 사업비를 산출하였다. 일곱째, 최적 저수지 위치와 규모로 유역면적 $739.57km^2$인 위치와 만수위 EL. 1,660 m, 총 저수량 3,529만 $m^3$인 규모를 제시하였다.

• Journal of The Geomorphological Association of Korea
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• v.24 no.1
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• pp.39-50
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• 2017

This study was conducted to analyze the variation of hydro-geomorphological environment along Baekgok wetland, which experiencing periodical inundation, in that water-level fluctuation of reservoir caused by irrigation. Since the field data is unavailable, modeling techniques, involving models such as HSPF and TELEMAC-2D, have been applied to simulate hydrological cycle in watershed and hydrodynamics in channel scale. The result of simulation indicates that the water-level of reservoir determines both the water surface extension and water depth in the wetland. Furthermore, it also shows that water-level functions as a spatial limit factor for a fluvial environment and woody vegetation such as willow. The fact of which the scale of water-level fluctuation being larger than an average topographical relief along the wetland can explain the result. While the water-level kept high, the wetland is submerged and waterbody becomes lentic. In contrast, while the water-level is lowered, fluvial phenomena of which being dependent on flow rate and channel shape become active. Hence, the valid fluvial process is likely to take place only for 4 months annually just near the channel, and it advances to a conclusion expecting a deposition to be dominant among the wetland except for such area. It is anticipated that such understanding can contribute to establishing plans to preserve the geomorphological and ecological value of the Baekgok wetland.